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PubMedDate not supplied

[Navigation in knee endoprosthesis implantation--preliminary experiences and prospective comparative study with conventional implantation technique].

OBJECTIVES: The efficiency of a computer-integrated instrumentation system in knee arthroplasty was evaluated and compared with a conventional instrumentation system. BACKGROUND: The OrthoPilot System defines the individual axis of the leg by means of an intraoperative kinematic analysis. LED's mounted on rigid bodies and screwed to the pelvis, femur and tibia are localized by a 3D infrared camera which is linked to a UNIX work station. The integrated calculation program leads to definition of the centres of hip, knee and ankle. Thereafter, LED-equipped alignment instruments allow definition of the femoral and tibial main resection planes. METHOD: The first sixty cases were included in the study. In addition, thirty cases each were entered into an OrthoPilot group and in a similar conventional control group. The navigated cohort consists of cases one to thirty, thus enclosing the "learning curve". RESULTS: Leg axes and femoral and tibial angles were assessed radiographically at the three-months postoperative control. Radiological measurements of the OrthoPilot group were clearly superior to those of the manual group. The differences, however, were not statistically different in the parameters "mechanical axis", "femoral axis lat." and "tibial axis ap.". With regard to the parameter "tibial axis lat." a significant difference in favour of the navigation system was observed. The measurements of "femoral axis ap." were insignificantly better in the manual group. In general, a slight tendency towards valgus positioning of the femoral components when using the navigation system has to be discussed. Complications influencing the clinical outcome did not occur. Additional time for navigation is calculated in a range of ten to fifteen minutes. CONCLUSIONS: The OrthoPilot system clearly facilitates proper alignment of endoprosthetic components in femur and tibia. Generally, the obtained values representing endoprosthetic alignment are superior to conventional technique. Marked deviations from ideal alignment can almost be avoided by means of the navigation system. During the learning curve the OrthoPilot system gained in reliability and reproducability.

Aged↗

PubMed2001

Cusum analysis of trends in operative selection and conversion rates for laparoscopic cholecystectomy.

BACKGROUND: Laparoscopic cholecystectomy (LC) requires a high degree of technical ability, spatial resolution and dexterity. Assessing trainees and competent operators is an important aspect of quality assurance in patient care. Most institutions quote mean conversion rate as a method of comparing operators' performance. The purpose of the present study was to use the technique of cumulative sum (cusum) analysis to determine whether a learning curve phenomenon exists in operators performing LC. METHODS: Data were obtained retrospectively by reviewing the operative records of all patients undergoing elective and acute cholecystectomy for a 30-month period coinciding with the commencement of LC at North Shore Hospital. Patients' age and gender, date and type of operative procedure, duration of operation, and name of operator were recorded. Mean and cusum-transformed data were derived for all operations as well as for four individual operators' performances. RESULTS: Over the study period a total of 614 cholecystectomies was performed, with 85% attempted laparoscopically. A total of 9.8% required conversion to the open technique. Time trend analysis with the cusum technique for all surgeons revealed an inverse relationship between selection rate and conversion rate. Analysis of four individual surgeons revealed three different time trend profiles. CONCLUSION: There was a direct inverse relationship between conversion rate and selection rate, in that careful selection is associated with a low conversion rate. Comparison of individual surgeons' performance showed wide variation, with only one surgeon exhibiting the phenomenon of a learning curve. Contrary to other reports, we found that performance on LC was not always related to operative experience. This highlights the need for a more objective method to analyse operator competence than operator experience alone.

Adolescent↗

PubMed2006

Stoppa procedure in bilateral inguinal hernia.

The Stoppa procedure is a very safe repair of bilateral inguinal hernia, but it requires a learning period to achieve optimal results. We present a study with our experience and learning curve for this technique. Two hundred and ten patients with bilateral inguinal hernia (420 hernias) were repaired with Stoppa procedure from January 1995 to December 2003 with an average age of 57.2 years (range 28-89 years), with 8 women and 202 men (96%). Emergency surgery was performed for incarcerated hernia in six cases (2.8%). The rates of recurrent hernias, concomitant disease and associated surgical techniques were similar in all the years. Operative time decreased from 100 min (1995) to 61-66 min (2001-2003). Drain remained in place in 100% (1995), and 0% (2003). Regional anaesthesia was performed in 25% (1995) and 80-90% in the last years; hospital stay decreased from 5.1 to 1.2 days (2003), and morbidity from 50% (1995) to 12-16% (P<0.0001). There were three recurrences, two in the first 30 cases (6.6%), and one in the remaining 180 (0.5%) (4-92 months follow-up). The procedure was introduced in 1995 by one surgeon, performing 100% of cases, being accepted progressively by other surgeons. The first 25-30 cases of a surgical technique are the learning curve, with the highest rate of morbidity, time, technical and operative difficulties, and long hospital stay. As a result of the first surgeon's experience, some modifications of the technique are developed and results improved.

Adult↗

PubMed2000

Laparoscopic Heller myotomy for achalasia.

BACKGROUND: Laparoscopic Heller myotomy provides similar results to open Heller myotomy for the treatment of oesophageal achalasia with the advantage of quicker recovery. The present series examines the evolution of operative technique, postoperative outcome and the effect of the 'learning curve' in a group of 70 consecutive patients. METHODS: Between 1992 and 1999, details of all patients undergoing oesophagogastric myotomy for achalasia were prospectively entered on a database. Patients were followed with a biannual postal symptom questionnaire and scores were obtained for dysphagia, heartburn, regurgitation and chest pain. Comparison between preoperative and postoperative symptom scores, and case number and operative complications was made using Fisher's exact test or Mann-Whitney U-test where appropriate. RESULTS: The indication for surgery was as a primary procedure in 20 cases; after failed endoscopic treatment in 48 cases; and after a 'failed' fundoplication in two cases. Myotomy was combined with a 360 degrees fundoplication in 57 patients and with an anterior fundoplication in 13 patients. Mucosal perforation occurred intraoperatively in 11 cases. Conversion to an open procedure was required in seven patients. Seven patients required a second operation. At a mean follow up of 2.9 years, symptom scores were significantly improved from preoperative values for dysphagia, regurgitation and chest pain (P < 0.001). There was no increase in the postoperative score for heartburn. The 'learning curve' contributed significantly to the length of the procedure, and the need for reoperation. CONCLUSIONS: Laparoscopic Heller myotomy is a technically challenging procedure that provides good early palliation of the symptoms associated with achalasia.

Adolescent↗

PubMed2002

The influence of new technologies on laparoscopic adrenalectomy: our personal experience with 91 patients.

BACKGROUND: Laparoscopic adrenalectomy has proved to be the technique of choice for managing benign pathologies of the adrenals and isolated adrenal metastases, especially those arising from lung tumor, but the procedure should not be performed for primitive adrenal carcinoma. The Authors wanted to test the advantages of the Harmonic Scalpel in laparoscopic adrenalectomy. METHODS: From April 1995 to April 2001, the authors investigated their series of laparoscopic adrenalectomies performed at the Careggi General Hospital, Division of General and Vascular Surgery, Florence, Italy. This study enrolled 91 patients with various adrenal pathologies. The transperitoneal approach was used, with the patient in a lateral position, as suggested by Gagner. Special care was taken to improve the surgical approach to the adrenals by the use of new technological devices such as the Harmonic Scalpel. The operative time required by the surgical procedure was computed by dividing the study into three periods: 1995-1997, 1998-1999, 2000-2001. The first period was necessary to complete the learning curve. In the second period, a steady state in surgical time was reached. During the third period, the Harmonic Scalpel was introduced. The differences between the three periods were tested using a nonparametric analysis (Mann-Whitney U test or Kruskal-Wallis test) as appropriate. A two-tailed p value of 0.05 or less was considered statistically significant. The authors investigated the cost of the operation performed in each of the two groups using, respectively, the conventional laparoscopic device (1998-1999) and the Harmonic Scalpel (2000-2001). The following expenses were considered: Harmonic Scalpel impulse generator and disposable shears, operating room cost per hour, and endoclip applier. RESULTS: The 91 laparoscopic adrenalectomies were performed with these indications: 31 incidentalomas (26 adenomas and 5 cysts), 25 cases of Conn's disease, 18 cases of Cushing's disease, 9 pheochromocytomas, 2 myelolipomas, 5 metastases (from lung, kidney, and breast) and 1 primitive carcinoma diagnosed preoperatively. Considering the whole series (1995-2001), there was a significant trend of reduction in operative time (p = 0.0001). Moreover looking at the first period (1995-1997), in which the learning curve was completed, the mean surgical time was 148 min, as compared with 125 mm. For the second period (1998-1999) (p = 0.0002). This represents a significant reduction in operative time. The authors noted a further reduction in the operative time when surgery was performed with the Harmonic Scalpel (2000-2001) (92 min; p = 0.001). The reduction in operative time attributable to the Harmonic Scalpel was confirmed also by a multivariate analysis of covariance general linear models procedure (GLM), which accounts for several confounders: age, gender, site and size of tumors, and histology (p = 0.0001). The rate was 3.3% for morbidity, 1.1% for mortality, and 2.2% for conversion. There was no difference in complications between patients treated with conventional devices and those treated with the Harmonic Scalpel. CONCLUSIONS: The laparoscopic approach has proved to be an extremely reliable procedure for benign pathologies and isolated metastases. There may yet be doubts about its use for the treatment of adrenal carcinomas preoperatively diagnosed. When surgery is performed using Harmonic Scalpel, operative time is significantly reduced and surgery is easier and less expensive. Infact use of the Harmonic Scalpel allowed the cost per operation to be reduced $70. Moreover, if surgery is performed using the nondisposable clip applier, the expenses are reduced $105.

Adolescent↗

PubMed2004

Total laparoscopic bypass for aortoiliac occlusive lesions: 93-case experience.

OBJECTIVES: We describe our experience with a new technique of total laparoscopic bypass surgery to treat aortoiliac occlusive lesions. MATERIAL AND METHODS: From November 2000 to December 2003, 93 total laparoscopic bypass procedures were performed to treat TASC (TransAtlantic Inter-Society Consensus document) grade C or D aortoiliac occlusive lesions. We also reimplanted 2 inferior mesenteric arteries, and performed 3 prosthesis-superior mesenteric bypasses and 2 suprarenal aorta endarterectomies. Our technique includes a sloping right lateral decubitus installation, which enables a simple transperitoneal left retrocolic or retrorenal approach to the infrarenal abdominal aorta. In patients with a hostile abdomen a retroperitoneal videoscopic approach was used. Aorta-prosthesis laparoscopic anastomoses are performed simply, which averts any trauma to the suture material. RESULTS: Patients included 76 men and 17 women, with median patient age 61 years (range, 38-79 years). The approach to the aorta was always possible, in particular, in obese patients. It enabled stable aortic exposure during performance of the laparoscopic aorta-prosthesis anastomosis. Median operative time was 240 minutes (range, 150-450 minutes). Median aortic clamping time measured to unclamping of the first prosthetic limb was 67.5 minutes (range, 30-135 minutes). Median duration of aorta-prosthesis anastomosis was 30 minutes (range, 12-90 minutes). The longest durations were mainly observed during the learning curve. Thirty-day postoperative mortality was 4% (4 of 93 patients). Two patients died of myocardial infarction. One patient with American Society of Anesthesiologists grade 4 disease operated on to treat critical ischemia died of multiple organ system failure, and 1 patient died of colonic ischemia. Major nonlethal postoperative complications were observed in 4 patients, and included lung atelectasia in 2 patients, graft infection in 1 patient operated on emergently to treat aortic occlusion, and secondary spleen rupture at day 5 in 1 patient. Median hospital stay was 7 days (range, 2-57 days). With a mean follow-up of 19 months (range, 1-37 months), complete recovery was observed in 89 patients, and all grafts were patent. One patient had kinking of a prosthetic limb at the groin, and in 1 patient Staphylococcus epidermidis graft infection developed, which was treated with in situ replacement with a rifampin-bonded graft. CONCLUSION: Total laparoscopic aortic bypass is feasible. In patients with TASC C and D aortoiliac occlusive lesions, short-term outcomes are comparable to those with conventional aortic bypass. After the initial learning curve, laparoscopic technique may reduce the operative trauma of aortic bypass.

Adult↗

PubMed1997

Stereotactic breast biopsy: a surgical series.

BACKGROUND: Stereotactic core needle biopsy (SCNB) is increasing in popularity and is currently being performed by both radiologists and surgeons. It has been shown to be accurate and cost effective, but the appropriate use of SCNB in the probably benign mammographic lesion has not been determined. Nor has it been determined whether a learning curve affects performance of the procedure. STUDY DESIGN: The records of all patients undergoing SCNB by the author from August 1993 through May 1996 were reviewed. Two hundred forty-two patients underwent 244 procedures. Indications for biopsy, results, and complications were examined. RESULTS: Probably benign mass was the most common indication for biopsy (45%), and microcalcifications were the indication for biopsy in 24%. A diagnosis of cancer was made in 11.1%. Patients with microcalcifications and probably benign masses were diagnosed with cancer in 18.4 and 1.8%, respectively. Three of eight patients undergoing open biopsy for atypical hyperplasia were diagnosed with cancer. Accuracy rate for the entire series was 97.7%. The effect of operator experience on the indication for SCNB was studied. As experience increased from the first to the last third of the study, microcalcifications as an indication increased from 23.5-37.5%. During this same time period, "probably benign" mass decreased from 53.1-32.5%. CONCLUSION: This study demonstrates that accuracy of this surgical series is comparable to other published series. Biopsies for more difficult lesions were noted to increase as operator experience increased. It was likely that this "learning curve" was owing to improvements in technique and an increased confidence in the accuracy of the procedure. With an incidence of cancer of less than 2% in patients with a probably benign mass, interval mammography represents for many, a cost-effective alternative.

Biopsy, Needle↗

PubMed2001

Description of two new human ovarian carcinoma models in nude rats suitable for laparoscopic experimentation.

BACKGROUND: Experimental laparoscopic trials require relevant models of ovarian carcinomatosis. METHODS: Female nude rats were inoculated intraperitoneally either with the IGR-OV1 or the NIH:OVCAR-3 human adenocarcinoma cell lines. Serial clinical checks and sacrifices were used to evaluate the rates of tumor take, survival, and patterns of tumor spread. Finally, laparoscopies with various pneumoperitoneum pressures were performed to verify the "surgical" relevancy of out models. The learning curve was measured. RESULTS: The best results were obtained when twenty-seven 106 IGR-OV1 cells and thirty-six 106 NIH:OVCAR-3 cells were injected in 28-day-old rats. The IGR-OV1 model provided a mean survival of 17.8 days (range, 13-22 days), with a high take rate (94%). The NIH:OVCAR-3 model resulted in a longer mean survival (59 days; range, 49-77) and also a high take rate (83%). The two models differed in their patterns of tumor spread: solid bulky omental metastasis having a diffuse microscopic peritoneal carcinomatosis with the IGR-OV1 line (the weight of the omental cake correlated significantly with the stage of development) and diffuse macroscopic peritoneal carcinomatosis having no large solid tumor, but visceral and paraaortic metastases, with the NIH:OVCAR-3 line. In both models, CA125 was high. Anesthesia could be performed and repeated in healthy and tumor-bearing rats. Laparoscopy was feasible, with pneumoperitoneum pressures as high as 8 mmHg lasting 1 h. Laparoscopy provided a reliable evaluation of the tumor spread into the peritoneal cavity. The plateau of the learning curve was soon obtained for take rate and survival after laparoscopy. CONCLUSION: We report two new human ovarian carcinoma xenografts in nude rats suitable for laparoscopy. The IGR-OV1 model mimics an advanced stage of the disease, and the NIH:OVCAR-3 model presents an earlier stage. These two models appear useful for experiments involving laparoscopy.

Adenocarcinoma↗

PubMed2002

Learning laparoscopic donor nephrectomy safely: a report on 100 cases.

HYPOTHESIS: There is concern that learning laparoscopic live donor nephrectomy (LLDN) is associated with increased morbidity. We propose that with a team approach LLDN can be learned safely, without increased donor morbidity or graft failure, even during the early portion of a learning curve. DESIGN: Case series with cohort comparison. SETTING: Tertiary referral center. PATIENTS: The laparoscopic group consisted of 100 donors and 100 recipients; the open group, 50 donors and 50 recipients. INTERVENTIONS: A team approach that combines laparoscopic and urologic expertise was used to perform 100 cases of LLDN. MAIN OUTCOME MEASURES: Donor morbidity and graft function in the laparoscopic group were compared with those in the open group. RESULTS: Laparoscopic live donor nephrectomy was completed in 99 patients. One patient required conversion to open donor nephrectomy because of intraoperative hemorrhage. Minor complications occurred in 6 laparoscopic group donors (6%) and 3 open group donors (6%). Laparoscopic and open group donors were of similar age. Operative times were longer for laparoscopic group donors (231 vs 209 minutes). Mean hospital stay was shorter for laparoscopic group donors (3.3 vs 4.7 days). Graft function was comparable between the laparoscopic and open groups, with equivalent postoperative creatinine levels. Graft survival was comparable. Recipient ureteral complications occurred with less frequency (2% vs 6%) in the laparoscopic group. CONCLUSIONS: By forming an operative team that combines expertise in laparoscopy with expertise in live donor nephrectomy, surgeons can learn LLDN safely. Adoption of the techniques developed by those who pioneered the procedure can further minimize the morbidity associated with a learning curve.

Adult↗

PubMed2002

The results of subintimal angioplasty in a district general hospital.

OBJECTIVES AND DESIGN: we report a prospective study to determine if subintimal angioplasty can be performed in non-teaching centres and to establish its learning curve. MATERIALS AND METHODS: subintimal angioplasty was performed on 50 limbs in 46 patients (34 male) with a median age of 72 years (range 45-93 years). Indication was critical limb ischaemia (27 limbs) or intermittent claudication (23 limbs). Occlusions were located in the superficial femoral artery in 44 limbs, popliteal artery in 4 limbs and the peroneal artery in two limbs. At a median of 7.9 months patients had colour duplex imaging of the vessels that underwent angioplasty to assess vessel patency. RESULTS: primary technical success was achieved in 39 cases (78%). Primary technical success was greater in the second group of 25 consecutive limbs to undergo angioplasty at 92% (23 cases) compared with the first 25 consecutive limbs at 64% (16 cases). At 6 months the overall vessel patency rate on duplex imaging was 57%, improving to 64% in the group having a primarily successful procedure. The equivalent rate of symptomatic improvement was 59 and 66% respectively. Complications occurred in five procedures, most were minor, but a single fatality was directly attributable to the procedure. CONCLUSION: subintimal angioplasty can reasonably be performed outside major teaching institutions. There is a short learning curve associated with the procedure.

Aged↗

PubMed2004

Results with titanium ossicular reconstruction prostheses.

OBJECTIVES/HYPOTHESIS: Despite the enthusiasm of recent short-term reviews, no center in the United States has published results meeting American Academy of Otolaryngology-Head and Neck Surgery guidelines with titanium-based prostheses. The purpose of the study was threefold. The first purpose was to review results with a titanium prosthesis system in cases meeting American Academy of Otolaryngology-Head and Neck Surgery reporting guidelines. The second was to compare these results with previously published results using non-titanium-based prostheses. The third was to examine the authors' results for any evidence of a "learning curve." STUDY DESIGN: Retrospective chart review was performed for the period from February 2000 to August 2001 and for the period from July 2002 to February 2003. METHODS: Of 313 cases, 130 consecutive cases were identified in the first period and 65 in the second time period. One hundred two patients had adequate follow-up for published guidelines. All cases were performed by the senior author (c.g.j.). Comparison data were obtained from a previous publication involving the senior author. RESULTS: Successful rehabilitation (<or=20 dB pure-tone average air-bone gap) of conductive hearing loss was obtained in 70% of partial ossicular chain reconstructions and 44% of total ossicular chain reconstructions when titanium prostheses were used. Comparison data revealed successful rehabilitation in 48% and 21% of non-titanium-based partial and total reconstructions, respectively. Postoperative pure-tone average air-bone gaps were not significantly different when compared with results in the period from July 2002 to February 2003. CONCLUSION: Newer titanium-based ossicular reconstruction devices represent an improvement over previously used non-titanium-based prostheses. The authors think that this improvement is realized rapidly because no learning curve existed in their data.

Bone Conduction↗

PubMedDate not supplied

A cost-effective technique for pure laparoscopic live donor nephrectomy.

OBJECTIVE: Compare two different techniques for laparoscopic live donor nephrectomy (LDN), related to the operative costs and learning curve. MATERIALS AND METHODS: Between April/2000 and October/2003, 61 patients were submitted to LDN in 2 different reference centers in kidney transplantation. At center A (CA), 11 patients were operated by a pure transperitoneal approach, using Hem-O-Lok clips for the renal pedicle control and the specimens were retrieved manually, without using endobags. At center B (CB), 50 patients were also operated by a pure transperitoneal approach, but the renal pedicles were controlled with endo-GIA appliers and the specimens were retrieved using endobags. RESULTS: Operative time (231 +/- 39 min vs. 179 +/- 30 min; p < 0.000), warm ischemia time (5.85 +/- 2.85 min vs. 3.84 +/- 3.84 min; p = 0.002) and blood loss (214 +/- 98 mL vs. 141 +/- 82 mL; p = 0.02) were statistically better in CB, when compared to CA. Discharge time was similar in both centers. One major complication was observed in both centers, leading to an open conversion in CA (9.1%). One donor death occurred in CB (2%). Regarding the recipients, no statistical difference was observed in all parameters analyzed. There was an economy of US$1.440 in each procedure performed in CA, when compared to CB. CONCLUSIONS: Despite the learning curve, the technique adopted by CA, showed no deleterious results to the donors and recipients when compared with the CB. On the other hand, this technique was cheaper than the technique performed in the CB, representing an attractive alternative for LDN, mainly in developing centers.

Cost-Benefit Analysis↗

PubMed2006

Influence of operator experience in radiofrequency ablation of malignant liver tumours on treatment outcome.

AIMS: Radiofrequency ablation is gaining popularity as the interventional therapy of choice for unresectable hepatic malignancies. However, little attention has been paid to the importance of operator experience in this therapy. This study aims to evaluate the results of RFA treatment dependent on operator experience and learning curve. PATIENTS AND METHODS: Between 2/2000 and 11/2004 we have undertaken 116 RFA procedures to ablate 404 unresectable primary or metastatic liver tumours in 84 patients. The clinical data of all patients were recorded prospectively and treatment results of the first 42 patients (group I) and the second 42 patients (group II) were compared. All patients were treated by the same surgeon or interventional radiologist. RESULTS: RFA was performed percutaneously in 44 procedures (group I n = 35, group II n = 9), via laparotomy in 64 procedures (group I n = 27, group II n = 37) and via laparoscopy in eight procedures (group I n = 1, group II n = 7). The complication rate was comparable in both groups with 7.9% in group I and 7.5% in group II. Group II had a higher complete ablation rate (96.2 vs 93.7%) than group I. One- and two-year survival rates of 92 and 89% in group II were significantly higher than in group I with 69 and 46% (p = 0.015). CONCLUSION: By the experience conditional optimization of indication and performance by a specialized RFA team the results could be improved significantly. The data on hand speak for a considerable learning curve in the RFA and demonstrate the importance of the experience of the therapist for the outcome of the patients.

Adult↗

PubMed1998

Hand-assisted laparoscopic sigmoidectomy for diverticulitis.

BACKGROUND: Sigmoid colectomy for diverticular disease, a routine procedure when performed using standard open methods, can prove much more challenging using minimum access techniques. Hand-assisted laparoscopic colectomy is a new technique that reportedly has a minimum learning curve, yet retains the benefits of a laparoscopic procedure. The purpose of this study was to perform and then prospectively to evaluate the outcome of this procedure on patients needing elective sigmoidectomy for diverticular disease. METHODS: Hand-assisted laparoscopic sigmoidectomy was performed on all patients undergoing elective sigmoidectomy for diverticular disease between January 18, 1996, and November 21, 1996. RESULTS: The study group consisted of six men and three women. Age averaged 50.8 (range, 39-66) years, weight averaged 183 (range, 150-224) pounds, and operation time averaged 3 hours and 42 minutes (range, 3-5 hours). No cases were converted to open methods. There were two minor postoperative complications (bleeding from the staple line, 1 patient; urinary retention, 1 patient; 22 percent). Resumption of flatus (which was the indication to start the patient on an oral diet) occurred between one and three (average, 1.44) days postoperatively. Patients were discharged from the hospital between one and three (average, 2.1) days postoperatively. Primary surgeon responsibility was distributed among four different surgeons, of which only the lead author previously had performed laparoscopic colectomy at this institution. CONCLUSIONS: Hand-assisted laparoscopic sigmoidectomy is a procedure that has a minimum learning curve, yet retains the benefits of a laparoscopic procedure.

Adult↗

PubMed1999

[Laparoscopic splenectomy for hematological diseases; results in 28 patients].

OBJECTIVE: To evaluate the first results of laparoscopic splenectomy for haematological diseases and the learning curve. DESIGN: Retrospective. PATIENTS AND METHODS: Data of all patients who underwent a laparoscopic splenectomy in October 1994-July 1998 in the University Hospital Rotterdam, Department of surgery, the Netherlands, were collected from electronic databases. Data on postoperative complications were collected from medical records. Patients with splenomegaly (> 15 cm) were not eligible for the procedure. RESULTS: 28 patients were eligible for a laparoscopic splenectomy. The male:female ratio was 1:4. The mean age was 35 years. The indications for surgery were idiopathic thrombocytopenic purpura (ITP; n = 24), Gilbert syndrome (n = 1), spherocytosis (n = 1), thalassaemia (n = 1) and haemolytic anaemia with ITP (n = 1). Conversion to an open procedure was necessary in 5 of 28 laparoscopic splenectomies (18%). The median operating time was 172 minutes. Complications occurred in four patients: pneumonia (n = 2), bleeding (n = 1) and urosepsis (n = 1). The median hospital stay was 5 days (range: 1-18). The first 14 laparoscopic splenectomies differed from the following 14 by a higher conversion rate (p = 0.01), a longer operation time (p = 0.002) and a longer hospital stay (p = 0.004). In 23 out of 25 patients with ITP the thrombocyte count became normal. CONCLUSION: Laparoscopic splenectomy is associated with a learning curve, with a high incidence of conversion in the early procedures. It appears to be a safe and effective operation.

Adolescent↗

PubMed2004

Use of a virtual reality simulator for ureteroscopy training.

PURPOSE: Virtual reality surgical simulators may shorten operative time and reduce the potential for iatrogenic injury by providing training outside the operating room. We hypothesized that training on a virtual ureteroscopy (VU) simulator would allow novice endoscopists to overcome the initial learning curve before entering the operating room. MATERIALS AND METHODS: We evaluated 16 medical students on their ability to perform specific ureteroscopic tasks on a VU simulator. The students trained on the simulator for a total of 5 hours over multiple sessions using different training modules and then were retested on the initial module. Likewise, 16 urology residents with varying degrees of endoscopic experience were assessed on the same test module twice, without additional simulator training. RESULTS: The students improved task completion time from 17.4 to 8.7 minutes (p <0.05), while the residents performed the task in 7.6 minutes at baseline and 6.7 minutes at the second trial. Stratification of residents by years of urology training revealed that the mean completion time for the students after training did not differ statistically from that of first year residents who had performed a median of 14 clinical ureteroscopies. Furthermore, the subjective performance scores of the students were comparable to those of the first year residents. CONCLUSIONS: Novice medical students trained on a VU simulator improved task completion time by 50% after training, and performed comparably to residents who had completed nearly 1 year of urology training. VR training may allow beginning urology residents to shorten the initial learning curve associated with ureteroscopy training, although this hypothesis requires further validation.

Adult↗

PubMed2006

Simplifying minimally invasive transhiatal esophagectomy with the inversion approach: Lessons learned from the first 20 cases.

HYPOTHESIS: The laparoscopic transhiatal esophagectomy can be simplified and performed safely and effectively by using a novel esophageal inversion technique. DESIGN: Case series describing technique, initial experience, and learning curve with laparoscopic inversion esophagectomy. SETTING: Tertiary care university hospital and veteran's hospital. PATIENTS: Twenty consecutive patients with high-grade dysplasia (n = 16) and esophageal adenocarcinoma (n = 4). INTERVENTION: Laparoscopic inversion esophagectomy, a totally laparoscopic approach to transhiatal esophagectomy that incorporates distal to proximal inversion to improve mediastinal exposure and ease of dissection. MAIN OUTCOME MEASURES: Perioperative end points and complications, compared between the first and second groups of 10 patients. RESULTS: There were 19 men and 1 woman. Median operative time was 448 minutes. Median blood loss was 175 cm3. Median intensive care unit stay was 4 days, and median total hospital stay was 9 days. Overall anastomotic leak rate was 20%. Five patients developed an anastomotic stricture, all successfully managed with endoscopic dilation. There were 2 recurrent laryngeal nerve injuries, which resolved. There was no intraoperative or 30-day mortality. Between the first 10 consecutive cases and last 10 procedures, the incidence of anastomotic leak and stricture formation decreased from 30% to 10% and 40% to 10%, respectively. During this period, the number of lymph nodes harvested increased 9-fold, and duration of intensive care unit stay decreased from 8.00 to 2.50 days. CONCLUSIONS: Laparoscopic inversion esophagectomy is a safe procedure. The learning curve for the inversion approach is approximately 10 operations in the hands of esophageal surgeons with advanced laparoscopic expertise.

Adenocarcinoma↗

PubMed2003

Laparoscopic donor nephrectomy at a low volume living donor transplant center: successful outcomes can be expected.

PURPOSE: Concern has been raised about possible increased morbidity associated with laparoscopic donor nephrectomy (LDN) during the learning curve of the procedure and at centers with a low volume of living donors. We evaluated the safety and success of LDN at a low volume living donor transplant center with a skilled laparoscopic urologist and experienced renal transplant team. MATERIALS AND METHODS: We reviewed the records of all patients who underwent LDN at our institution. A single surgeon skilled in laparoscopy (JAC) performed all LDNs. Patient demographics, operative reports, complications and recipient outcomes were evaluated. RESULTS: A total of 17 LDNs were performed between January 2000 and September 2002. There was 1 elective conversion to an open procedure for kidney harvest due to complex hilar anatomy. Only 1 minor complication occurred (wound seroma) and 1 donor had creatinine persistently elevated to 1.9 mg/dl (normal 0.6 to 1.2). Mean operating room time, estimated blood loss and hospital stay were 250 minutes, 188 ml and 2.5 days, respectively. Recipient creatinine had a nadir mean of 1.2 mg/dl and a 90-day postoperative mean of 1.6 mg/dl. One recipient eventually lost the graft due to recurrent disease. CONCLUSIONS: LDN can be performed safely and efficiently at low volume transplant centers with a skilled laparoscopist and experienced renal transplant team. Laparoscopic skills developed during similar procedures, such as laparoscopic radical and partial nephrectomy, minimize the learning curve and morbidity of LDN to produce results consistent with those in the published literature.

Adult↗